Annie Dookhan changed her plea Friday in Suffolk Superior Court on charges of obstruction of justice, perjury and tampering with evidence. She was sentenced to three to five years in prison, followed by two years' probation.

JORGE QUIROGA, WCVB NEWSCENTER5. A DISGRACED FORMER STATE LAB CHEMIST IS HEADING TO PRISON. ANNIE DOOKHAN PLEAD GUILTY. ANNIE DOOKHAN CREATED HAVOC FOR SIX COUNTIES AND MAY HAVE COMPROMISED AS MANY AS 40,000 CASES AND COST THE STATE MILLIONS OF DOLLARS. TODAY SHE PUBLICLY ACKNOWLEDGED THE DAMAGE SHE CAUSE. SHE ADMITTED GUILT, TAMPERING WITH EVIDENCE AND PERJURY. OVER 14 YEARS, DOOKHAN ALTERED DRUG TESTS AND SKIPPED STEPS IN THE TESTING PROCESS. I FIND THAT THE PLEA IS OFFERED WILLINGLY AND VOLUNTARILY. SHE WAS SENTENCED TO THREE TO FIVE YEARS. MORE THAN THE GUIDELINES SUGGEST, LESS THAN WHAT THE ATTORNEY GENERAL WANTED. THE IMPACT ACROSS THE COMMONWEALTH ON THESE CASES AND THE PUBLIC TRUST HAS BEEN DEVASTATING. WE ARE WORKING TO FIX IT. AMONG THE 300 PRISONERS RELEASED BECAUSE OF DOOKHAN'S TAMPERING, 22-YEAR-OLD DONTA HOOD WHO WAS ARRESTED SIX MONTHS LATER AND CHARGED WITH KILLING A MAN. WE HAVE NEVER SEEN ANYTHING OF THIS SCOPE IN MASSACHUSETTS AND I DON'T BELIEVE THERE HAS BEEN A BIGGER FORENSIC SCIENCE SCANDAL NATIONWIDE. HANDCUFFED, DOOKHAN WAS IMMEDIATELY TAKEN INTO CUSTODY AND TRANSPORTED TO M.C.I. FRAMINGHAM. HER PARENTS REFUSED COMMENT AS THEY TRIED TO LEAVE THE COURTHOUSE SURROUNDED BY THE MEDIA. THE STORY GOES ON FOR THE THOUSANDS OF INDIVIDUALS WHO STILL HAVE YET TO HAVE THEIR DAY IN COURT. THE OTHER SHOE WILL FALL WHEN THE INSPECTOR GENERAL RELEASES A REPORT ON THE OVERALL PROBLEMS HERE AT DRUG